U.S. patent number 4,716,938 [Application Number 06/862,936] was granted by the patent office on 1988-01-05 for pressure-tight plug coupling.
Invention is credited to Erwin Weh, Wolfgang Weh.
United States Patent |
4,716,938 |
Weh , et al. |
January 5, 1988 |
Pressure-tight plug coupling
Abstract
A plug coupling for providing a pressure-sealed connection to a
device provided with a connecting member comprising a cylindrical
housing; a piston shiftable within the housing clamping jaws
connected to the piston and concentrially arranged around the
longitudinal axis of the housing and radially displaceable by means
of a ramp arrangement by an axial movement of the piston relative
to the housing; pressure is applied to said piston for moving it in
longitudinal direction of the housing thereby pressing the clamping
jaws radially inwards or outwards by means of said ramp
arrangement. The free ends of the clamping jaws are moved into an
engaging position for engagement with said connecting member.
Inventors: |
Weh; Erwin (D-7918 Illertissen,
DE), Weh; Wolfgang (D-7918 Illertissen,
DE) |
Family
ID: |
25832374 |
Appl.
No.: |
06/862,936 |
Filed: |
May 14, 1986 |
Foreign Application Priority Data
|
|
|
|
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May 20, 1985 [DE] |
|
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3518019 |
Oct 16, 1985 [DE] |
|
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3536916 |
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Current U.S.
Class: |
138/93;
137/614.06; 138/89; 285/102 |
Current CPC
Class: |
F16L
55/136 (20130101); F16L 37/1215 (20130101); Y10T
137/87973 (20150401) |
Current International
Class: |
F16L
37/00 (20060101); F16L 37/12 (20060101); F16L
55/10 (20060101); F16L 55/136 (20060101); F16L
037/28 () |
Field of
Search: |
;138/89,93
;285/34,35,102,921,306,83,101,322,323,316 ;73/49.8 ;141/342
;137/614.06 ;251/149.9 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Recla; Henry J.
Assistant Examiner: Peters; L. J.
Attorney, Agent or Firm: Armstrong, Nikaido, Marmelstein
& Kubovcik
Claims
We claim:
1. A plug coupling for providing a pressure-sealed connection to a
device provided with threaded connecting means having a front face
surface comprising:
a cylindrical housing provided at an open front side, with a
surface corresponding to that of said connecting means, and having
a rear side closed by closure member;
a core element axially extending in said housing having a rear end
fixed to said closure member and having a front end extending into
the region of the face surface of the housing;
a piston means within said housing slidably mounted on the core
element for axial movement;
elongated clamping jaws having first ends linked to a front portion
of said piston, and extending in a generally axial direction, said
clamping jaws being concentrically arranged around a longitudinal
axis of said housing and having free second ends radially
displaceable;
ramp means for rocking said clamping jaws about joints between said
first ends of said clamping jaws and said front portion of said
piston upon an axial movement of said piston;
means for applying pressure to said piston for moving it in said
axial direction of said housing thereby pressing said clamping jaws
radially inwards by means of a ramp arrangment and axial movement
thereof toward said front end of said housing for displacing said
free ends of said clamping jaws by an engagement thereof with said
ramp means into a radial position permitting a threading provided
at said free ends of said clamping jaws to be placed in radial
jaxtaposition to a threading of said threaded connecting means;
a spring means biasing said piston against the pressure of said
pressure means and moving said piston toward said rear end of said
housing upon release of the pressure of said pressure means;
a means for positively engaging said threading of said free ends of
said clamping jaws into said threaded connecting means and
positively maintaining an engagement of said clamping jaws with
said threading of said connecting means upon movement of said
piston toward said rear end of said housing; and sealing means
provided for engagement with said face surface of said front end of
said housing and for pressure-tight sealing engagement to said face
surface of said threaded connecting means upon movement of said
piston toward said rear end of said housing.
2. The plug coupling of claim 1 wherein said spring means is a
spiral spring means wound around a rear portion of said piston.
3. The plug coupling of claim 1 wherein said pressure means is a
hand lever pivotally mounted at said housing and acting upon said
piston in longitudinal direction of said housing.
4. The plug coupling of claim 1 wherein said pressure means is a
gaseous pressure means connectable to a rear end of said housing
and provided with a closure member for selectively applying gaseous
pressure against a rear end of said piston.
5. The plug coupling of claim 1 wherein front portions of said plug
coupling are easily exchangable.
6. The plug coupling of claim 5 wherein a front portion of said
housing is in threaded connection to a main body of said
housing.
7. The plug coupling of claim 5 wherein said clamping jaws are
releaseable connected to said piston.
8. The plug coupling of claim 7 wherein said clamping jaws are in a
hooked-in connection to said piston.
9. The plug coupling of claim 7 wherein said clamping jaws are
formed as relatively rigid parts with an increased hardness.
10. The plug coupling of claim 1 wherein said housing is provided
near a front portion with a connecting means for applying a
pressurized fluid.
11. The plug coupling of claim 1 wherein said spring means is
arranged between a locking ring supported by an annular rim
provided at an inner surface of said housing and a flange formed at
a rear end of said piston.
12. The plug coupling of claim 1 wherein said ramp arrangement is
provided between an outer peripheral surface of said clamping jaws
and an inner surface of said housing.
13. The plug coupling of claim 1 wherein said clamping jaws are
provided with threadings at the exterior of front parts
thereof.
14. The plug coupling of claim 1 wherein said clamping jaws are
provided with threading at the interior of front parts thereof.
15. A plug coupling for providing a pressure-sealed connection to a
device provided with connecting means having a front face surface
comprising:
a cylindrical housing provided, at an open front side, with a
surface corresponding to that of said connecting means, and having
a rear side closed by a closure member;
a piston means slideably mounted on the core element for axial
movement within said housing;
a core element axially extending in said housing having a rear end
fixed to said closure member and having a front end extending into
the region of the face surface of the housing;
elongated clamping jaws having first ends linked to a front portion
of said piston, and extending in a generally axial direction, said
clamping jaws being concentrically arranged about a longitudinal
axis of said housing and having free second ends of said clamping
jaws radially displaceable;
ramp means for rocking said clamping jaws about joints between said
first ends of said clamping jaws and said front portion of said
piston upon an axial movement of said piston;
means for applying pressure to said piston axial movement thereof
toward said front end of said housing for displacing said free ends
of said clamping jaws by an engagement thereof with said ramp means
into a radial position permitting said free ends of said clamping
jaws to be placed in radial juxtaposition to said connecting
means;
a spring means for moving said piston toward said rear end of said
housing upon release of the pressure of said pressure means
a means for positively urging said free ends of said clamping jaws
into radial engagement with said connecting means and positively
maintaining a radial engagement of said clamping jaws with said
connecting means upon movement of said piston toward said rear end
of said housing; and
sealing means provided for engagement with said face surface of
said front end of said housing and for pressure-tight sealing
engagement to said face surface of said connecting means upon
movement of said piston toward said rear end of said housing.
16. The coupling of claim 15 wherein said housing is provided near
a front portion with a connecting means for applying a pressurized
fluid.
17. The plug coupling of claim 15 wherein said ramp arrangement is
provided between an outer peripheral surface of said clamping jaws
and an inner surface of said housing.
18. The plug coupling of claim I5 wherein said clamping jaws are
provided with engaging means at the exterior of front parts
thereof.
19. The plug coupling of claim 15 wherein said clamping jaws are
provided with engaging means at the interior of front parts
thereof.
20. The plug coupling of claim 15 wherein a front portion of said
housing is in threaded connection to a main body of said plug
coupling.
21. A plug coupling for providing a pressure-sealed connection to a
device provided with connecting means comprising:
a cylindrilcal housing,
a piston shiftable within said housing,
clamping jaws, connected to a front portion of said piston
concentrically arranged around longitudinal axis of said housing
and having free ends radially displaceable by means of a ramp
arrangement upon an axial movement of said piston in an axial
direction in said housing,
a hand lever pivotally mounted at said housing and acting upon said
piston for moving it in said axial direction of said housing
thereby pressing said clamping jaws radially by means of said ramp
arrangement;
a spring means biasing said piston against said pressure means;
and
a means for moving said free ends of said clamping jaws in an
engaging position for engagement with said connecting means.
22. A plug coupling for providing a pressure sealed connection to a
device provided with a connecting means having a front face surface
comprising:
a cylindrical housing provided, at an open front side, with a
surface corresponding to that of said connecting means, and having
a rear side closed by a closure member;
a core element axially extending in said housing having a rear end
fixed to said closure member and having a front end extending into
the region of the face surface of the housing;
a piston means slideably mounted on the core element for axial
movement within said housing;
elongated clamping jaws extending from a front portion of said
piston, in a generally axial direction, said clamping jaws being
concentrically arranged around a longitudinal axis of said housing
and having free ends radially displaceable by means of a ramp
arrangement upon an axial movement of the piston in;
means for applying pressure to said piston for axial movement
thereof toward said front end of said housing for displacing said
free ends of said clamping jaws by an engagement thereof with said
ramp means into a radial position permitting said free ends of said
clamping jaws to be placed in radial juxtaposition to said
connecting means;
a spring means for moving said piston toward said rear end of said
housing upon release of the pressure of said pressure means;
a means for positively urging said free ends of said clamping into
radial engagement with said connecting means and positively
maintaining a radial engagement of clamping jaws with said
connecting means upon movement of said piston toward said rear end
of said housing; and
sealing means provided for engagement with said face surface of
said front end of said housing and for pressure-tight sealing
engagement to said face surface of said connecting means upon
movement of said piston toward said rear end of said housing;
and
a lateral supply connection at a front part of said housing for
supply a pressurized liquid to said connecting means.
23. A plug coupling for providing a pressure-sealed connection to a
device provided with connecting means having a front face surface
comprising:
a cylindrical housing provided, at an open front side, with a
surface corresponding to that of said connecting means, and having
a rear side closed by a closure member;
a piston means slideably mounted on the core element for axial
movement within said housing;
a core element axially extending in said housing having a rear end
fixed to said closure member and having a front end extending into
the region of the face surface of the housing;
elongated clamping jaws having first ends linked to a front portion
of said piston, and extending in a generally axial direction, said
clamping jaws being concentrically arranged about a longitudinal
axis of said housing and having free second ends of said clamping
jaws radially displaceable;
ramp means for rocking said clamping jaws about joints between said
first ends of said clamping jaws and said front portion of said
piston upon an axial movement of said piston;
means for applying pressure to said piston for axial movement
thereof toward said front end of said housing for displacing said
free ends of said clamping jaws by an engagement thereof with said
ramp means into a radial position permitting said free ends of said
clamping jaws to be placed in radial juxtaposition to said
connecting means;
a means for moving said piston toward said rear end of said housing
upon release of the pressure of pressure means;
a means for positively urging said free ends of said clamping jaws
into radial engagement with said connecting means and positively
maintaining a radial engagement of said clamping jaws with said
connecting means upon movement of said piston toward said rear end
of said housing; and
sealing means provided for engagement with said face surface of
said front end of said housing and for pressure-tight sealing
engagement to said face surface of said connecting means upon
movement of said piston toward said rear end of said housing;
said clamping jaws being hooked-in with their rear ends in a
peripheral recess of said piston.
24. A plug coupling for providing a pressure-sealed connection to a
device provided with connecting means having a front face surface
comprising;
a cylindrical housing provided, at an open front side, with a
surface corresponding to that of said connecting means, and having
a rear side closed by a closure member;
a piston means slideably mounted on the core element for axial
movement within said housing;
a core element axially extending in said housing having a rear end
fixed to said closure member and having a front end extending into
the region of the face surface of the housing;
elongated clamping jaws having first ends linked to a front portion
of said piston, and extending in a generally axial direction, said
clamping jaws being concentrically arranged about a longitudinal
axis of said housing and having free second ends of clamping jaws
radially displaceable.,
ramp means for rocking said clamping jaws about joints between said
first ends of said clamping jaws and said front portion of said
piston upon an axial movement of said piston;
means for applying pressure to said piston for axial movement
thereof toward said front end of said housing for displacing said
free ends of said clamping jaws by an engagement thereof with said
ramp means into a radial position permitting said free ends of said
clamping jaws to be placed in radial juxtaposition to said
connecting means;
a means for moving said piston toward said rear end of said housing
upon release of the pressure of pressure means;
a means for positively urging said free ends of said clamping into
radial engagement with said connecting means and positively
maintaining a radial engagement of said clamping jaws with said
connecting means upon movement of said piston toward said rear end
of said housing; and
sealing means provided for engagement with said face surface of
said front end of said housing and for pressure-tight sealing
engagement to said face surface of said connecting means upon
movement of said piston toward said rear end of said housing
said clamping jaws being formed as segments and are provided with
radially inward projected flanges engaging an annular recess formed
on an outer surface of said piston.
25. A plug coupling for providing a pressure-sealed connection to a
device provided with connecting means having a front face surface
comprising:
a cylindrical housing provided, at an open front side, with a
surface corresponding to that of said connecting means, and having
a rear side closed by a closure member;
a piston means slideably mounted on the core element for axial
movement within said housing;
a core element axially extending in said housing having a rear end
fixed to said closure member and having a front end extending into
the region of the face surface of the housing;
elongated clamping jaws having first ends linked to a front portion
of said piston, and extending in a generally axial direction, said
clamping jaws being concentrically arranged about a longitudinal
axis of said housing and having free second ends of said clamping
jaws radially displaceable;
ramp means for rocking said clamping jaws about joints between said
first ends of said clamping jaws and said front portion of said
piston upon an axial movement of said piston;
means for applying pressure to said piston for axial movement
thereof toward said front end of said housing for displacing said
free ends of said clamping jaws by an engagement thereof with said
ramp means into a radial position permitting said free ends of said
clamping jaws to be placed in radial juxtaposition to said
connecting means;
a means for moving said piston toward said rear end of said housing
upon release of the pressure of pressure means;
a means for positively urging said free ends of said clamping jaws
into radial engagement with said connecting means and positively
maintaining a radial engagement of said clamping jaws with said
connecting means upon movement of said piston toward said rear end
of said housing; and
sealing means provided for engagement with said face surface of
said front end of said housing and for pressure-tight sealing
engagement to said face surface of said connecting means upon
movement of said piston toward said rear end of said housing;
said clamping jaws being exchangeable by clamping jaws of different
shape.
Description
FIELD OF THE INVENTION
The invention relates to a pressure-tight plug coupling for
providing a pressure-sealed connection to a device provided with
connecting means. Such plug couplings are of particular use for a
fast and one-handed application to and removal from a connector
provided at a device of use. Exemplary, pressure sensitive elements
may be tested by momentary application of a pressurized medium by
means of a plug coupling.
BACKGROUND OF THE ART
In our U.S. Pat. No. 4,543,995, corresponding to the International
patent application WO No. 84/02566 we have disclosed a plug
coupling of the type definded before comprising a cylindrical
housing, a piston shiftable within said housing and having formed
at its front end clamping jaws extending out of said housing and
radially displaceable via a ramp arrangement upon axial movement of
the piston relative to the housing the movement being effected by
selectively connecting a pressure source to one of various
compartments formed between the inner surface of the housing and
the piston by shifting a sleeve along the outer surface of the
housing. Though such a plug coupling is easy and fast to handle and
operates safely, the sleeve surrounding the housing has a
relatively large outer diameter which makes it difficult to use the
coupling in cases of closely arranged connections. Furthermore,
providing the various radial bores is complicated and several
sealings are required for sealing the various compartments against
each other.
The U.S. Pat. No. 2,388,179 discloses a plug coupling using
clamping jaws which may be radially widened, but are fixed to a
tube. After inserting of a threaded connection the clamping jaws
are pressed radially inward by a sleeve which is shiftable along
the tapered outer surfaces of the clamping jaws. Such a plug
coupling cannot be used one-handed. Furthermore, it is necessary to
turn the coupling for getting a pressure-tight connection.
According to a further aspect the clamping jaws of the plug
coupling according to U.S. Pat. No. 4,543,995 are unitary with the
piston which requires a relatively thin transition between the
piston and clamping jaws which have to be resilient. Thus, there is
a tendency of breakage of the clamping jaws at the transition point
upon heavy use of the coupling. Furthermore, a certain force is
necessary to overcome the resiliency of the clamping jaws when
pressing them together.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a plug coupling
having a simplified design. It is another object of the invention
to provide a plug coupling having a reduced outer diameter. It is a
further object of the invention to provide a plug coupling which
may easily be adapted to various different connectors. A still
further object of the invention is to provide a plug coupling
having a longer life time. Still a further object of the invention
is to provide a plug coupling which needs a reduced force
application.
These and other objects of the invention are accomplished by a plug
coupling for providing a pressure-sealed connection to a device
provided with connecting means comprising a cylindrical housing, a
piston shiftable within said housing, clamping jaws connected to
said piston and concentrically arranged around the longitudinal
axis of said housing and radially displaceable by means of a ramp
arrangement by an axial movement of the piston relative to the
housing, a means for applying pressure to said piston for moving it
in longitudinal direction of said housing thereby pressing said
clamping jaws radially inwards by means of a said ramp arrangement
and a spring means biasing said piston against said pressure
means.
According to another aspect of the present invention a plug
coupling for providing a pressur-sealed connection to a device
provided with connecting means comprises a cylindrical housing, a
piston shiftable within said housing, a plurality of clamping jaws
concentrically arranged about a longitudinal axis of said housing
and engaging a front portion of said piston for longitudinal
movement therewith, free ends of said clamping jaws being radially
displaceable via a ramp arrangement during movement of said piston
in an outward direction of said longitudinal axis in respect of
said housing, and a means for applying pressure to said piston in
order to move said clamping jaws in either of a connected and a
disconnected position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational, partially sectional view of a first
embodiment of a plug coupling explaining the situation where the
coupling may be inserted into a threaded opening;
FIG. 2 is a view similar to that of FIG. 1 illustrating a
modification of the first embodiment of the coupling according to
the invention in the connected situation;
FIG. 3 is a view similar to that of FIG. 1 of a second embodiment
of the plug coupling according to the invention again in connected
position;
FIGS. 4a and 4b are elevational sectional views of modified inner
parts of the second embodiment;
FIG. 5 a schematic diagram in front view for illustrating the
mounting of the clamping jaws of the second embodiment;
FIG. 6 a sectional elvational view of a third embodiment of the
plug coupling according to the invention;
FIG. 7 a sectional elevational view of a fourth embodiment of the
plug coupling according to the invention;
FIG. 8 a sectional elevational view of plug coupling according to
the invention as a modification of the plug coupling according to
FIG. 7; and
FIG. 9 a sectional elevational view of a fifth embodiment of the
plug coupling according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
Since we have described in detail the principal elements of the
plug coupling in our U.S. Pat. No. 4,543,995 the following
description relates on the main to the modified elements of the new
plug coupling which exemplary may serve for a connection to a
connecting member of any kind of device.
FIG. 1 shows a housing 12 in which a piston 14 sealed by a sealing
22 against the housing 12 is shiftable in the direction of the
longitudinal axis of the housing relative thereto on a core 16
sealed in respect of the piston 14 by a further sealing 24. The
front opening of the housing 12 is tapered such that an inner ramp
33 is formed.
The front end of the piston 14 is subdivided into a plurality of
clamping jaws 26, preferably 6 which are resilient in radial
direction. With the embodiment the clamping jaws 26 are provided
with an outer threading 27 at their free ends. The exterior surface
of the clamping jaws are provided with ramps 32 engaging the ramps
33 formed at the inner surface of the housing 12. Thus, the ramps
32 slide on the ramp 33 and the clamping jaws 26 are pressed
together when the piston 14 is moved to the left (FIG. 1) out of
the housing 12.
Between the threading 27 and the ramps 32 there is an annular
recess 29 into which a third sealing 28 is inserted which fits with
its outer peripheral surface into an annular recess 30 at the end
face of the housing 12.
The sealing 22 is inserted preferably in the middle of the length
of the piston between two annular flanges 23 and 25. A locking ring
38 engages an inner rim of the housing 12 through which locking
ring the piston 14 slides with a cylindrically recessed portion 39
when moved in longitudinal direction. The rear end of the piston 14
is provided with an end face flange 42. In the space between the
locking ring 38 and the flange 42 a spiral spring 20 is provided
which tends to move the piston into the interior of the housing 12.
A rod 40 pressed against the outer end face of the flange 42 by a
hand lever 18 via a roll 48 acts against the pressure of the spiral
spring 20. The hand lever 18 is pivotally mounted at the housing 12
at a point 50.
Specifically, the housing is closed at its rear end by a threaded
member 51 through which the rod 40 is inserted and which is
provided with pivotal point 50. In a central bore 53 of the
threaded member the central core 16 is screwed in, whose front end
34 is formed cylindrically and extends into the front region of the
clamping jaws 26. These clamping jaws 26 are provided at their
inner surfaces with ramps 37 and an opening 36. Upon the movement
of the piston 14 into the housing 12 the ramps 37 slide at the face
edge of the cylindrically front end portion 34 of the core 16.
Thus, the clamping jaws 26 are positively widened in radial
direction and locked in the end position of the piston 14 in which
position the front end 34 is located in the opening 36. In this
position the third sealing 28 is located in the recess 30 (viz.FIG.
2).
The operation of the plug coupling according to the first
embodiment is as follows:
In the situation according to FIG. 1 the hand lever 18 is pressed
against the outer surface of the housing 12 and the piston 14 is in
a position where its front end bearing the clamping jaws 26 is
urged out of the housing 12. As may be seen from FIG. 1 the
clamping jaws 26 are pressed radially inwards in view of the
co-operation of the ramps 32 and 33. The coupling is now inserted
into a plug provided with an inner threading to such an extent that
the face end of the plug approximately engages the sealing 28.
Releasing of the hand lever 18 causes its rocking away from the
outer surface of the housing 12 as illustrated in FIG. 2 by the
pressure of the spiral spring 20. In this position the clamping
jaws 26 are maintained in their widened position tightly engaging
the inner threading of the plug (not shown). The third sealing 28
is pressed into the recess 30 which results in a pressure tight
connection. It may be appreciated, that such a connection may be
made within an extremely short time. Also, the connection may be
released immediately by pressing hand lever 18 again.
Whilst the first embodiment according to FIG. 1 explains the use of
a coupling according to the invention as a momentary plug for
closing a threaded opening the modification according to FIG. 2
explains a coupling where an inlet 70 preferably provided with a
threading is attached preferably perpendicular to the longitudinal
axis of the coupling near the front end of the housing 12 such that
a space 66 provided between the first sealing 22 and the third
sealing 28 may be supplied with a pressurized fluid preferably
hydraulic liquid for application of that fluid to a device, for
instance, for test purposes upon connecting the coupling to a
threaded opening of the device to be tested alternatively, the
fluid may be gaseous.
FIG. 3 shows a second embodiment of the coupling according to the
invention where the hand lever 18 is replaced by a pressure source
(not shown) which may be connected to the coupling through a
threaded opening 62 provided in an end member 60 attached at the
rear end of the housing 12. The end member 60 is provided with a
passage 68 such that upon application of pressure a face 64 of the
flange 42 has pressure applied thereto. Consequently, a piston 114
is shifted from the position shown in FIG. 3 to the left into a
position as shown in FIG. 1. Upon removal of the pressure the
spiral spring 20 returns the piston 114 into the position according
to FIG. 3. Application and removal of pressure may be accomplished
by a pedal switch. Thus, the attaching and removal of the coupling
may be done in an extremely short time. It should be noted that the
inlet 70 shown in FIG. 2 may be provided as well for the coupling
of the second embodiment.
Furthermore, whilst the first and second embodiments show a
connection using clamping jaws for inner threadings the arrangement
may be such as explained in W0 No. 84/02566 for a connection to an
opening provided with an outer threading.
Also, the coupling according to the invention is not only
applicable for connection by a threading but for any other
connector. In this case it is only necessary to adapt the clamping
jaws in particular their free ends for an appropriate engagement.
For instance, the clamping jaws may be provided at their free ends
with radial extension which grip behind an annular rim provided at
the face of the member to which the coupling should be connected.
Thus, with the piston 114 moving inwards the rim is tightly pressed
against the third sealing 28 at the face edge of the housing
12.
The second embodiment of the invention is provided with further
favourable features. As may be seen from FIG. 3 a front part 152 of
the housing may be exchangable by means of threadings 113. Thus, it
may be easily replaced by a different front part 152 adapted at its
front end to a different connecting member.
Furthermore, clamping jaws 126 are not unitary with the piston 114.
Rather, the clamping jaws 126 are individual elements which are in
engagement with the piston 114 such that they have restricted free
movement in radial direction whilst there is a minimum movement in
longitudinal direction in respect of the piston 114. With such a
design the clamping jaws need not be resilient and it is possible
to harden them to rockwell values scale C, even above 50.
Furthermore, there is no need of applying larger forces for
pressing the clamping jaws together. Also, there is no relatively
weak transition between the piston 14 and the clamping jaws 26 as
in FIG. 1 which tends to break after heavy use.
The FIGS. 4a and 4b show a preferred design for connecting the
individual clamping jaws 126 to the piston 114. Specifically, the
rear ends of the clamping jaws are provided with segmented,
hooklike inwardly extending projections 47 (see also FIG. 5) which
engage an anular recess 44 provided at the outer periphery of the
front end of the piston 114. As may be seen from FIG. 5 the
projections 47 of the clamping jaws 126 are arranged in a circle
and kept apart by studs 50 arranged in gaps 48 between the
individual segments. It may be appreciated that there is no or
little movement in longitudinal direction. On the other hand it may
be seen from FIG. 3 that there is some radial movement possible
which is restricted by the inner surface of the housing 12 such
that the segmented jaws 126 are prevented from hooking out of the
recess 44. Thus, the front ends of the clamping jaws are free to be
moved radially inwardly and outwardly without any biasing spring
action.
Various further constructions of the coupling region between the
clamping jaws and the piston are available to a person skilled in
the art. The main point is that the clamping jaws 126 and the
piston 114 are connected to each other such that there is a certain
mobility in radial direction whilst there is no or little mobility
in longitudinal direction between the two elements. Exemplary, the
clamping jaws 126 might overlie the piston 114 and may be connected
by radial pins to the latter. Alternatively, the rear ends of the
clamping jaws may be provided with radially extending parts which
are losely fixed to the front end face of the piston 114.
FIG. 4a illustrates clamping jaws 126 which are secured to the
piston 114 against movement in peripheral direction by pins 150
extending radially in radial holes 152 provided in the front ends
of the piston 114 and holes 154 provided at the inner side of the
clamping jaws 126. The clamping jaws 126 are further secured
against a radial movement of their rear ends by an O-ring 156.
FIG. 4b shows a modification of the connection between the clamping
jaws 126a and a piston 114a. With this embodiment pins 158
extending parallel to the longitudinal axis pass through respective
holes provided at the front end of the piston 114a and the inward
projections 46 provided at the rear ends of the clamping jaws
126a.
It should be noted that with many types of connections between the
clamping jaws and the piston an easy changing of the jaws is
possible. Also, the seperation between the clamping jaws and the
piston may be applied to all embodiments of WO No. 84/02566 and the
first embodiment of the present invention.
FIG. 4b illustrates that the clamping jaws 126 having a threading
27 may be easily replaced by clamping jaws 126a having a different
threading 27a.
FIG. 6 shows a third embodiment of the present invention using a
shiftable sleeve 4 for air pressure application as explained in
detail in our U.S. Pat. No. 4,543,995 for operating the coupling
according to the invention by shifting the piston 214 forth and
back by applying air pressure onto different sides of the piston
214. With this embodiment similar to the first embodiment modified
according to FIG. 2 it is possible to apply a pressurized fluid
through an opening 170 to the connected device. Also, with this
third embodiment the front parts are easy exchangable, in
particular a front portion 252 of the housing, a front part 216 of
the core 16 and a front part 214 having formed at its front end
clamping jaws 226. Preferably these releasable connections are
threadings 213, 220 and 221.
It should be noted that it would be possible with the second
embodiment to insert an air pressure sleeve design according to our
U.S. Pat. No. 4,543,995 between an air pressure source and the end
member 60 of the coupling according to FIG. 3. This would enable a
one-hand-operation of the coupling without any foot control of the
air pressure source.
Again it should be noted that as mentioned in connection with the
first and second embodiments all couplings may be designed such
that they are applicable for connections with outer threadings,
inner threadings or other connecting designs.
FIG. 7 illustrates a fourth embodiment of a plug coupling according
to the invention adapted for use with external threaded
connections. In principle, the plug coupling of the fourth
embodiment is similar to that explained in connection with FIG. 2.
Thus, for similar parts similar reference numerals are used. With
the fourth embodiment a core 216 is provided with a central bore
280 at its front part. Radial holes 286 connect the central bore
280 to a cylindrical space 266 via further radial holes 284
provided in middle part of piston 214. The space 266 may be
supplied from a fluid source through connecting member 270.
Clamping jaws 326 are connected to the front end of the piston 214
in a manner similar to that of FIG. 4a using an O-ring 256 for
maintaining the clamping jaws together which are secured to the
front end of the piston 214 by radial pins 250.
A recessed space 276 between the inner surface of the clamping jaws
and the front part of the core 216 is occupied by sealing support
member 272 supporting a front face sealing 274. The space 276 is of
such a size that it permits a restricted longitudinal movement of
the sealing support member relative to the clamping jaws 326. The
closing and opening of clamping jaws 326 is accomplished by the
ramp arrangement 232,233 during inward movement of the piston 214
into the housing 312. A sealing 282 is provided between the
external front end of the core 216 and the inner cylindrical
surface of the sealing support member 272.
In operation, when pressing the handle 18 into the position shown
in FIG. 7 the piston 214 is moved relative to the housing 312. Upon
this movement the clamping jaws 326 are released from the clamping
arrangement 232,233 and will open by radial displacement in view of
the tension provided by the O-ring 256. The sealing support member
272 is moved together with the clamping jaws 326. Now, the coupling
is brought into engagement with the desired connection the sealing
274 contacting the front face of the connection.
When releasing handle 18 the spring 20 moves the piston 214 back
into the housing 312 the ramp arrangement 232, 233 closing the
clamping jaws positively. In the inner end position the core front
face urges the sealing support members 272 and the sealing 274
against the front face of the connection.
Now, when fluid preferably an hydraulic oil or air is supplied via
connecting member 270 to space 266 this fluid is passed through the
central board 280 to the connected device. Simultaneously a
pressure is exerted to the flange 223. Thus this fluid pressure
supplements the action of the spring 20 to maintain the plug
coupling in the closed position. For release the fluid supply is
stopped and the handle 18 is again pressed into the position shown
in FIG. 7.
In a modification of the fourth embodiment of FIG. 7 the supply of
fluid to the connected device is considerably increased by a design
according to FIG. 8 with this modified embodiment a core 316 has a
considerably enlarged front part 316a such that a cylindrical
concentrical opening 318 therein has a diameter in the range of the
connection 300 in a conical transitional part 316b between the rear
part of the core 316 and its front part 316a relatively large
openings 320 are provided for passing a large quantity of fluid
from a connecting member 370 to the opening 318.
A further transition between the rear part of the piston 314 and
its front part 314a offers a large pressure area 314b for tightly
fixing the arrangement in the closed position.
FIG. 9 shows a further embodiment of the plug coupling according to
the invention using a clamping jaws and piston arrangement
according to FIG. 4a and a control by means of sleeve 4 according
to the embodiment of FIG. 6. The front part corresponse to that of
the device according to FIG. 7 with some slight modifications.
FIG. 9 shows a situation where the clamping jaws 326 are not yet
fully housed in a housing 412 but shortly before the final closing
position.
Compared with the device according to FIG. 7 the core 218 is
extended through a connection sealing 374 secured to a sealing
support member 372 which in the open condition abuts with its rear
side against an annular radial surface 390 of the clamping jaws
326. In the closed position the sealing support member 372 engages
a stop 388 whereby the connection sealing 374 is tightly pressed
against the connection member (not shown). The central opening of
the sealing 374 is of such a diameter that it tightly fits onto the
outer surface of the core 280. As regards the operating part of the
plug coupling a fluid preferably air is applied through a central
threaded bore 362 in a rear member 360. The bore 362 is connected
through radial ducts to the outer surface of the rear member 360
covered by the sleeve 4. Depending on the position of the sleeve 4
air is then passed either to a pressure chamber 366 for moving the
piston 314 and the clamping jaws 326 into the housing 412 or via a
duct 376 to a pressure chamber 372 in order to move the clamping
jaws 426 out of the housing 412 or through a duct 378 (as shown) to
a chamber 392 which is connected to the central bore 280 of the
core 316 through the wholes 284 and 286 as described in connection
with FIG. 7. In this situation as shown in FIG. 9 pressure is still
supplied to the pressure chamber 366 thus that the piston 314 is
still displaced until the clamping jaws 326 are essentially (but
not fully) within the housing 412.
In the forgoing description various embodiments of plug couplings
have been explained having different operating and connecting
units. It should be noted that every operating unit as the sleeve
operated unit, the handlever operated unit and the pressure and
spring operated unit may be combined with different connection
units adapted for a connection with internal or external threads or
any other desired tight sealing connection as exemplary shown in
FIG. 8.
Exemplary, it would be possible with the plug coupling of the
second embodiment to insert an air pressure sleeve design according
to our U.S. Pat. No. 4,543,995 between an air pressure source and
an end member 60 of the coupling according to FIG. 3. This would
enable a one-hand operation of the coupling without any foot
control of the air pressure source.
It should be noted that the term "pressure" should be understood in
a broader sense including for instance the application of a force
exerted by spring.
* * * * *